--- /dev/null
+/*
+ * CXL Flash Device Driver
+ *
+ * Written by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>, IBM Corporation
+ * Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
+ *
+ * Copyright (C) 2015 IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/syscalls.h>
+#include <misc/cxl.h>
+#include <asm/unaligned.h>
+#include <asm/bitsperlong.h>
+
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_host.h>
+#include <uapi/scsi/cxlflash_ioctl.h>
+
+#include "sislite.h"
+#include "common.h"
+#include "vlun.h"
+#include "superpipe.h"
+
+/**
+ * marshal_virt_to_resize() - translate uvirtual to resize structure
+ * @virt: Source structure from which to translate/copy.
+ * @resize: Destination structure for the translate/copy.
+ */
+static void marshal_virt_to_resize(struct dk_cxlflash_uvirtual *virt,
+ struct dk_cxlflash_resize *resize)
+{
+ resize->hdr = virt->hdr;
+ resize->context_id = virt->context_id;
+ resize->rsrc_handle = virt->rsrc_handle;
+ resize->req_size = virt->lun_size;
+ resize->last_lba = virt->last_lba;
+}
+
+/**
+ * marshal_clone_to_rele() - translate clone to release structure
+ * @clone: Source structure from which to translate/copy.
+ * @rele: Destination structure for the translate/copy.
+ */
+static void marshal_clone_to_rele(struct dk_cxlflash_clone *clone,
+ struct dk_cxlflash_release *release)
+{
+ release->hdr = clone->hdr;
+ release->context_id = clone->context_id_dst;
+}
+
+/**
+ * ba_init() - initializes a block allocator
+ * @ba_lun: Block allocator to initialize.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ba_init(struct ba_lun *ba_lun)
+{
+ struct ba_lun_info *bali = NULL;
+ int lun_size_au = 0, i = 0;
+ int last_word_underflow = 0;
+ u64 *lam;
+
+ pr_debug("%s: Initializing LUN: lun_id = %llX, "
+ "ba_lun->lsize = %lX, ba_lun->au_size = %lX\n",
+ __func__, ba_lun->lun_id, ba_lun->lsize, ba_lun->au_size);
+
+ /* Calculate bit map size */
+ lun_size_au = ba_lun->lsize / ba_lun->au_size;
+ if (lun_size_au == 0) {
+ pr_debug("%s: Requested LUN size of 0!\n", __func__);
+ return -EINVAL;
+ }
+
+ /* Allocate lun information container */
+ bali = kzalloc(sizeof(struct ba_lun_info), GFP_KERNEL);
+ if (unlikely(!bali)) {
+ pr_err("%s: Failed to allocate lun_info for lun_id %llX\n",
+ __func__, ba_lun->lun_id);
+ return -ENOMEM;
+ }
+
+ bali->total_aus = lun_size_au;
+ bali->lun_bmap_size = lun_size_au / BITS_PER_LONG;
+
+ if (lun_size_au % BITS_PER_LONG)
+ bali->lun_bmap_size++;
+
+ /* Allocate bitmap space */
+ bali->lun_alloc_map = kzalloc((bali->lun_bmap_size * sizeof(u64)),
+ GFP_KERNEL);
+ if (unlikely(!bali->lun_alloc_map)) {
+ pr_err("%s: Failed to allocate lun allocation map: "
+ "lun_id = %llX\n", __func__, ba_lun->lun_id);
+ kfree(bali);
+ return -ENOMEM;
+ }
+
+ /* Initialize the bit map size and set all bits to '1' */
+ bali->free_aun_cnt = lun_size_au;
+
+ for (i = 0; i < bali->lun_bmap_size; i++)
+ bali->lun_alloc_map[i] = 0xFFFFFFFFFFFFFFFFULL;
+
+ /* If the last word not fully utilized, mark extra bits as allocated */
+ last_word_underflow = (bali->lun_bmap_size * BITS_PER_LONG);
+ last_word_underflow -= bali->free_aun_cnt;
+ if (last_word_underflow > 0) {
+ lam = &bali->lun_alloc_map[bali->lun_bmap_size - 1];
+ for (i = (HIBIT - last_word_underflow + 1);
+ i < BITS_PER_LONG;
+ i++)
+ clear_bit(i, (ulong *)lam);
+ }
+
+ /* Initialize high elevator index, low/curr already at 0 from kzalloc */
+ bali->free_high_idx = bali->lun_bmap_size;
+
+ /* Allocate clone map */
+ bali->aun_clone_map = kzalloc((bali->total_aus * sizeof(u8)),
+ GFP_KERNEL);
+ if (unlikely(!bali->aun_clone_map)) {
+ pr_err("%s: Failed to allocate clone map: lun_id = %llX\n",
+ __func__, ba_lun->lun_id);
+ kfree(bali->lun_alloc_map);
+ kfree(bali);
+ return -ENOMEM;
+ }
+
+ /* Pass the allocated LUN info as a handle to the user */
+ ba_lun->ba_lun_handle = bali;
+
+ pr_debug("%s: Successfully initialized the LUN: "
+ "lun_id = %llX, bitmap size = %X, free_aun_cnt = %llX\n",
+ __func__, ba_lun->lun_id, bali->lun_bmap_size,
+ bali->free_aun_cnt);
+ return 0;
+}
+
+/**
+ * find_free_range() - locates a free bit within the block allocator
+ * @low: First word in block allocator to start search.
+ * @high: Last word in block allocator to search.
+ * @bali: LUN information structure owning the block allocator to search.
+ * @bit_word: Passes back the word in the block allocator owning the free bit.
+ *
+ * Return: The bit position within the passed back word, -1 on failure
+ */
+static int find_free_range(u32 low,
+ u32 high,
+ struct ba_lun_info *bali, int *bit_word)
+{
+ int i;
+ u64 bit_pos = -1;
+ ulong *lam, num_bits;
+
+ for (i = low; i < high; i++)
+ if (bali->lun_alloc_map[i] != 0) {
+ lam = (ulong *)&bali->lun_alloc_map[i];
+ num_bits = (sizeof(*lam) * BITS_PER_BYTE);
+ bit_pos = find_first_bit(lam, num_bits);
+
+ pr_devel("%s: Found free bit %llX in LUN "
+ "map entry %llX at bitmap index = %X\n",
+ __func__, bit_pos, bali->lun_alloc_map[i],
+ i);
+
+ *bit_word = i;
+ bali->free_aun_cnt--;
+ clear_bit(bit_pos, lam);
+ break;
+ }
+
+ return bit_pos;
+}
+
+/**
+ * ba_alloc() - allocates a block from the block allocator
+ * @ba_lun: Block allocator from which to allocate a block.
+ *
+ * Return: The allocated block, -1 on failure
+ */
+static u64 ba_alloc(struct ba_lun *ba_lun)
+{
+ u64 bit_pos = -1;
+ int bit_word = 0;
+ struct ba_lun_info *bali = NULL;
+
+ bali = ba_lun->ba_lun_handle;
+
+ pr_debug("%s: Received block allocation request: "
+ "lun_id = %llX, free_aun_cnt = %llX\n",
+ __func__, ba_lun->lun_id, bali->free_aun_cnt);
+
+ if (bali->free_aun_cnt == 0) {
+ pr_debug("%s: No space left on LUN: lun_id = %llX\n",
+ __func__, ba_lun->lun_id);
+ return -1ULL;
+ }
+
+ /* Search to find a free entry, curr->high then low->curr */
+ bit_pos = find_free_range(bali->free_curr_idx,
+ bali->free_high_idx, bali, &bit_word);
+ if (bit_pos == -1) {
+ bit_pos = find_free_range(bali->free_low_idx,
+ bali->free_curr_idx,
+ bali, &bit_word);
+ if (bit_pos == -1) {
+ pr_debug("%s: Could not find an allocation unit on LUN:"
+ " lun_id = %llX\n", __func__, ba_lun->lun_id);
+ return -1ULL;
+ }
+ }
+
+ /* Update the free_curr_idx */
+ if (bit_pos == HIBIT)
+ bali->free_curr_idx = bit_word + 1;
+ else
+ bali->free_curr_idx = bit_word;
+
+ pr_debug("%s: Allocating AU number %llX, on lun_id %llX, "
+ "free_aun_cnt = %llX\n", __func__,
+ ((bit_word * BITS_PER_LONG) + bit_pos), ba_lun->lun_id,
+ bali->free_aun_cnt);
+
+ return (u64) ((bit_word * BITS_PER_LONG) + bit_pos);
+}
+
+/**
+ * validate_alloc() - validates the specified block has been allocated
+ * @ba_lun_info: LUN info owning the block allocator.
+ * @aun: Block to validate.
+ *
+ * Return: 0 on success, -1 on failure
+ */
+static int validate_alloc(struct ba_lun_info *bali, u64 aun)
+{
+ int idx = 0, bit_pos = 0;
+
+ idx = aun / BITS_PER_LONG;
+ bit_pos = aun % BITS_PER_LONG;
+
+ if (test_bit(bit_pos, (ulong *)&bali->lun_alloc_map[idx]))
+ return -1;
+
+ return 0;
+}
+
+/**
+ * ba_free() - frees a block from the block allocator
+ * @ba_lun: Block allocator from which to allocate a block.
+ * @to_free: Block to free.
+ *
+ * Return: 0 on success, -1 on failure
+ */
+static int ba_free(struct ba_lun *ba_lun, u64 to_free)
+{
+ int idx = 0, bit_pos = 0;
+ struct ba_lun_info *bali = NULL;
+
+ bali = ba_lun->ba_lun_handle;
+
+ if (validate_alloc(bali, to_free)) {
+ pr_debug("%s: The AUN %llX is not allocated on lun_id %llX\n",
+ __func__, to_free, ba_lun->lun_id);
+ return -1;
+ }
+
+ pr_debug("%s: Received a request to free AU %llX on lun_id %llX, "
+ "free_aun_cnt = %llX\n", __func__, to_free, ba_lun->lun_id,
+ bali->free_aun_cnt);
+
+ if (bali->aun_clone_map[to_free] > 0) {
+ pr_debug("%s: AUN %llX on lun_id %llX has been cloned. Clone "
+ "count = %X\n", __func__, to_free, ba_lun->lun_id,
+ bali->aun_clone_map[to_free]);
+ bali->aun_clone_map[to_free]--;
+ return 0;
+ }
+
+ idx = to_free / BITS_PER_LONG;
+ bit_pos = to_free % BITS_PER_LONG;
+
+ set_bit(bit_pos, (ulong *)&bali->lun_alloc_map[idx]);
+ bali->free_aun_cnt++;
+
+ if (idx < bali->free_low_idx)
+ bali->free_low_idx = idx;
+ else if (idx > bali->free_high_idx)
+ bali->free_high_idx = idx;
+
+ pr_debug("%s: Successfully freed AU at bit_pos %X, bit map index %X on "
+ "lun_id %llX, free_aun_cnt = %llX\n", __func__, bit_pos, idx,
+ ba_lun->lun_id, bali->free_aun_cnt);
+
+ return 0;
+}
+
+/**
+ * ba_clone() - Clone a chunk of the block allocation table
+ * @ba_lun: Block allocator from which to allocate a block.
+ * @to_free: Block to free.
+ *
+ * Return: 0 on success, -1 on failure
+ */
+static int ba_clone(struct ba_lun *ba_lun, u64 to_clone)
+{
+ struct ba_lun_info *bali = ba_lun->ba_lun_handle;
+
+ if (validate_alloc(bali, to_clone)) {
+ pr_debug("%s: AUN %llX is not allocated on lun_id %llX\n",
+ __func__, to_clone, ba_lun->lun_id);
+ return -1;
+ }
+
+ pr_debug("%s: Received a request to clone AUN %llX on lun_id %llX\n",
+ __func__, to_clone, ba_lun->lun_id);
+
+ if (bali->aun_clone_map[to_clone] == MAX_AUN_CLONE_CNT) {
+ pr_debug("%s: AUN %llX on lun_id %llX hit max clones already\n",
+ __func__, to_clone, ba_lun->lun_id);
+ return -1;
+ }
+
+ bali->aun_clone_map[to_clone]++;
+
+ return 0;
+}
+
+/**
+ * ba_space() - returns the amount of free space left in the block allocator
+ * @ba_lun: Block allocator.
+ *
+ * Return: Amount of free space in block allocator
+ */
+static u64 ba_space(struct ba_lun *ba_lun)
+{
+ struct ba_lun_info *bali = ba_lun->ba_lun_handle;
+
+ return bali->free_aun_cnt;
+}
+
+/**
+ * cxlflash_ba_terminate() - frees resources associated with the block allocator
+ * @ba_lun: Block allocator.
+ *
+ * Safe to call in a partially allocated state.
+ */
+void cxlflash_ba_terminate(struct ba_lun *ba_lun)
+{
+ struct ba_lun_info *bali = ba_lun->ba_lun_handle;
+
+ if (bali) {
+ kfree(bali->aun_clone_map);
+ kfree(bali->lun_alloc_map);
+ kfree(bali);
+ ba_lun->ba_lun_handle = NULL;
+ }
+}
+
+/**
+ * init_vlun() - initializes a LUN for virtual use
+ * @lun_info: LUN information structure that owns the block allocator.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int init_vlun(struct llun_info *lli)
+{
+ int rc = 0;
+ struct glun_info *gli = lli->parent;
+ struct blka *blka = &gli->blka;
+
+ memset(blka, 0, sizeof(*blka));
+ mutex_init(&blka->mutex);
+
+ /* LUN IDs are unique per port, save the index instead */
+ blka->ba_lun.lun_id = lli->lun_index;
+ blka->ba_lun.lsize = gli->max_lba + 1;
+ blka->ba_lun.lba_size = gli->blk_len;
+
+ blka->ba_lun.au_size = MC_CHUNK_SIZE;
+ blka->nchunk = blka->ba_lun.lsize / MC_CHUNK_SIZE;
+
+ rc = ba_init(&blka->ba_lun);
+ if (unlikely(rc))
+ pr_debug("%s: cannot init block_alloc, rc=%d\n", __func__, rc);
+
+ pr_debug("%s: returning rc=%d lli=%p\n", __func__, rc, lli);
+ return rc;
+}
+
+/**
+ * write_same16() - sends a SCSI WRITE_SAME16 (0) command to specified LUN
+ * @sdev: SCSI device associated with LUN.
+ * @lba: Logical block address to start write same.
+ * @nblks: Number of logical blocks to write same.
+ *
+ * The SCSI WRITE_SAME16 can take quite a while to complete. Should an EEH occur
+ * while in scsi_execute(), the EEH handler will attempt to recover. As part of
+ * the recovery, the handler drains all currently running ioctls, waiting until
+ * they have completed before proceeding with a reset. As this routine is used
+ * on the ioctl path, this can create a condition where the EEH handler becomes
+ * stuck, infinitely waiting for this ioctl thread. To avoid this behavior,
+ * temporarily unmark this thread as an ioctl thread by releasing the ioctl read
+ * semaphore. This will allow the EEH handler to proceed with a recovery while
+ * this thread is still running. Once the scsi_execute() returns, reacquire the
+ * ioctl read semaphore and check the adapter state in case it changed while
+ * inside of scsi_execute(). The state check will wait if the adapter is still
+ * being recovered or return a failure if the recovery failed. In the event that
+ * the adapter reset failed, simply return the failure as the ioctl would be
+ * unable to continue.
+ *
+ * Note that the above puts a requirement on this routine to only be called on
+ * an ioctl thread.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int write_same16(struct scsi_device *sdev,
+ u64 lba,
+ u32 nblks)
+{
+ u8 *cmd_buf = NULL;
+ u8 *scsi_cmd = NULL;
+ u8 *sense_buf = NULL;
+ int rc = 0;
+ int result = 0;
+ int ws_limit = SISLITE_MAX_WS_BLOCKS;
+ u64 offset = lba;
+ int left = nblks;
+ u32 to = sdev->request_queue->rq_timeout;
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+
+ cmd_buf = kzalloc(CMD_BUFSIZE, GFP_KERNEL);
+ scsi_cmd = kzalloc(MAX_COMMAND_SIZE, GFP_KERNEL);
+ sense_buf = kzalloc(SCSI_SENSE_BUFFERSIZE, GFP_KERNEL);
+ if (unlikely(!cmd_buf || !scsi_cmd || !sense_buf)) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ while (left > 0) {
+
+ scsi_cmd[0] = WRITE_SAME_16;
+ put_unaligned_be64(offset, &scsi_cmd[2]);
+ put_unaligned_be32(ws_limit < left ? ws_limit : left,
+ &scsi_cmd[10]);
+
+ /* Drop the ioctl read semahpore across lengthy call */
+ up_read(&cfg->ioctl_rwsem);
+ result = scsi_execute(sdev, scsi_cmd, DMA_TO_DEVICE, cmd_buf,
+ CMD_BUFSIZE, sense_buf, to, CMD_RETRIES,
+ 0, NULL);
+ down_read(&cfg->ioctl_rwsem);
+ rc = check_state(cfg);
+ if (rc) {
+ dev_err(dev, "%s: Failed state! result=0x08%X\n",
+ __func__, result);
+ rc = -ENODEV;
+ goto out;
+ }
+
+ if (result) {
+ dev_err_ratelimited(dev, "%s: command failed for "
+ "offset %lld result=0x%x\n",
+ __func__, offset, result);
+ rc = -EIO;
+ goto out;
+ }
+ left -= ws_limit;
+ offset += ws_limit;
+ }
+
+out:
+ kfree(cmd_buf);
+ kfree(scsi_cmd);
+ kfree(sense_buf);
+ pr_debug("%s: returning rc=%d\n", __func__, rc);
+ return rc;
+}
+
+/**
+ * grow_lxt() - expands the translation table associated with the specified RHTE
+ * @afu: AFU associated with the host.
+ * @sdev: SCSI device associated with LUN.
+ * @ctxid: Context ID of context owning the RHTE.
+ * @rhndl: Resource handle associated with the RHTE.
+ * @rhte: Resource handle entry (RHTE).
+ * @new_size: Number of translation entries associated with RHTE.
+ *
+ * By design, this routine employs a 'best attempt' allocation and will
+ * truncate the requested size down if there is not sufficient space in
+ * the block allocator to satisfy the request but there does exist some
+ * amount of space. The user is made aware of this by returning the size
+ * allocated.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int grow_lxt(struct afu *afu,
+ struct scsi_device *sdev,
+ ctx_hndl_t ctxid,
+ res_hndl_t rhndl,
+ struct sisl_rht_entry *rhte,
+ u64 *new_size)
+{
+ struct sisl_lxt_entry *lxt = NULL, *lxt_old = NULL;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+ struct blka *blka = &gli->blka;
+ u32 av_size;
+ u32 ngrps, ngrps_old;
+ u64 aun; /* chunk# allocated by block allocator */
+ u64 delta = *new_size - rhte->lxt_cnt;
+ u64 my_new_size;
+ int i, rc = 0;
+
+ /*
+ * Check what is available in the block allocator before re-allocating
+ * LXT array. This is done up front under the mutex which must not be
+ * released until after allocation is complete.
+ */
+ mutex_lock(&blka->mutex);
+ av_size = ba_space(&blka->ba_lun);
+ if (unlikely(av_size <= 0)) {
+ pr_debug("%s: ba_space error: av_size %d\n", __func__, av_size);
+ mutex_unlock(&blka->mutex);
+ rc = -ENOSPC;
+ goto out;
+ }
+
+ if (av_size < delta)
+ delta = av_size;
+
+ lxt_old = rhte->lxt_start;
+ ngrps_old = LXT_NUM_GROUPS(rhte->lxt_cnt);
+ ngrps = LXT_NUM_GROUPS(rhte->lxt_cnt + delta);
+
+ if (ngrps != ngrps_old) {
+ /* reallocate to fit new size */
+ lxt = kzalloc((sizeof(*lxt) * LXT_GROUP_SIZE * ngrps),
+ GFP_KERNEL);
+ if (unlikely(!lxt)) {
+ mutex_unlock(&blka->mutex);
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ /* copy over all old entries */
+ memcpy(lxt, lxt_old, (sizeof(*lxt) * rhte->lxt_cnt));
+ } else
+ lxt = lxt_old;
+
+ /* nothing can fail from now on */
+ my_new_size = rhte->lxt_cnt + delta;
+
+ /* add new entries to the end */
+ for (i = rhte->lxt_cnt; i < my_new_size; i++) {
+ /*
+ * Due to the earlier check of available space, ba_alloc
+ * cannot fail here. If it did due to internal error,
+ * leave a rlba_base of -1u which will likely be a
+ * invalid LUN (too large).
+ */
+ aun = ba_alloc(&blka->ba_lun);
+ if ((aun == -1ULL) || (aun >= blka->nchunk))
+ pr_debug("%s: ba_alloc error: allocated chunk# %llX, "
+ "max %llX\n", __func__, aun, blka->nchunk - 1);
+
+ /* select both ports, use r/w perms from RHT */
+ lxt[i].rlba_base = ((aun << MC_CHUNK_SHIFT) |
+ (lli->lun_index << LXT_LUNIDX_SHIFT) |
+ (RHT_PERM_RW << LXT_PERM_SHIFT |
+ lli->port_sel));
+ }
+
+ mutex_unlock(&blka->mutex);
+
+ /*
+ * The following sequence is prescribed in the SISlite spec
+ * for syncing up with the AFU when adding LXT entries.
+ */
+ dma_wmb(); /* Make LXT updates are visible */
+
+ rhte->lxt_start = lxt;
+ dma_wmb(); /* Make RHT entry's LXT table update visible */
+
+ rhte->lxt_cnt = my_new_size;
+ dma_wmb(); /* Make RHT entry's LXT table size update visible */
+
+ cxlflash_afu_sync(afu, ctxid, rhndl, AFU_LW_SYNC);
+
+ /* free old lxt if reallocated */
+ if (lxt != lxt_old)
+ kfree(lxt_old);
+ *new_size = my_new_size;
+out:
+ pr_debug("%s: returning rc=%d\n", __func__, rc);
+ return rc;
+}
+
+/**
+ * shrink_lxt() - reduces translation table associated with the specified RHTE
+ * @afu: AFU associated with the host.
+ * @sdev: SCSI device associated with LUN.
+ * @rhndl: Resource handle associated with the RHTE.
+ * @rhte: Resource handle entry (RHTE).
+ * @ctxi: Context owning resources.
+ * @new_size: Number of translation entries associated with RHTE.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int shrink_lxt(struct afu *afu,
+ struct scsi_device *sdev,
+ res_hndl_t rhndl,
+ struct sisl_rht_entry *rhte,
+ struct ctx_info *ctxi,
+ u64 *new_size)
+{
+ struct sisl_lxt_entry *lxt, *lxt_old;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+ struct blka *blka = &gli->blka;
+ ctx_hndl_t ctxid = DECODE_CTXID(ctxi->ctxid);
+ bool needs_ws = ctxi->rht_needs_ws[rhndl];
+ bool needs_sync = !ctxi->err_recovery_active;
+ u32 ngrps, ngrps_old;
+ u64 aun; /* chunk# allocated by block allocator */
+ u64 delta = rhte->lxt_cnt - *new_size;
+ u64 my_new_size;
+ int i, rc = 0;
+
+ lxt_old = rhte->lxt_start;
+ ngrps_old = LXT_NUM_GROUPS(rhte->lxt_cnt);
+ ngrps = LXT_NUM_GROUPS(rhte->lxt_cnt - delta);
+
+ if (ngrps != ngrps_old) {
+ /* Reallocate to fit new size unless new size is 0 */
+ if (ngrps) {
+ lxt = kzalloc((sizeof(*lxt) * LXT_GROUP_SIZE * ngrps),
+ GFP_KERNEL);
+ if (unlikely(!lxt)) {
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ /* Copy over old entries that will remain */
+ memcpy(lxt, lxt_old,
+ (sizeof(*lxt) * (rhte->lxt_cnt - delta)));
+ } else
+ lxt = NULL;
+ } else
+ lxt = lxt_old;
+
+ /* Nothing can fail from now on */
+ my_new_size = rhte->lxt_cnt - delta;
+
+ /*
+ * The following sequence is prescribed in the SISlite spec
+ * for syncing up with the AFU when removing LXT entries.
+ */
+ rhte->lxt_cnt = my_new_size;
+ dma_wmb(); /* Make RHT entry's LXT table size update visible */
+
+ rhte->lxt_start = lxt;
+ dma_wmb(); /* Make RHT entry's LXT table update visible */
+
+ if (needs_sync)
+ cxlflash_afu_sync(afu, ctxid, rhndl, AFU_HW_SYNC);
+
+ if (needs_ws) {
+ /*
+ * Mark the context as unavailable, so that we can release
+ * the mutex safely.
+ */
+ ctxi->unavail = true;
+ mutex_unlock(&ctxi->mutex);
+ }
+
+ /* Free LBAs allocated to freed chunks */
+ mutex_lock(&blka->mutex);
+ for (i = delta - 1; i >= 0; i--) {
+ /* Mask the higher 48 bits before shifting, even though
+ * it is a noop
+ */
+ aun = (lxt_old[my_new_size + i].rlba_base & SISL_ASTATUS_MASK);
+ aun = (aun >> MC_CHUNK_SHIFT);
+ if (needs_ws)
+ write_same16(sdev, aun, MC_CHUNK_SIZE);
+ ba_free(&blka->ba_lun, aun);
+ }
+ mutex_unlock(&blka->mutex);
+
+ if (needs_ws) {
+ /* Make the context visible again */
+ mutex_lock(&ctxi->mutex);
+ ctxi->unavail = false;
+ }
+
+ /* Free old lxt if reallocated */
+ if (lxt != lxt_old)
+ kfree(lxt_old);
+ *new_size = my_new_size;
+out:
+ pr_debug("%s: returning rc=%d\n", __func__, rc);
+ return rc;
+}
+
+/**
+ * _cxlflash_vlun_resize() - changes the size of a virtual LUN
+ * @sdev: SCSI device associated with LUN owning virtual LUN.
+ * @ctxi: Context owning resources.
+ * @resize: Resize ioctl data structure.
+ *
+ * On successful return, the user is informed of the new size (in blocks)
+ * of the virtual LUN in last LBA format. When the size of the virtual
+ * LUN is zero, the last LBA is reflected as -1. See comment in the
+ * prologue for _cxlflash_disk_release() regarding AFU syncs and contexts
+ * on the error recovery list.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+int _cxlflash_vlun_resize(struct scsi_device *sdev,
+ struct ctx_info *ctxi,
+ struct dk_cxlflash_resize *resize)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+ struct afu *afu = cfg->afu;
+ bool put_ctx = false;
+
+ res_hndl_t rhndl = resize->rsrc_handle;
+ u64 new_size;
+ u64 nsectors;
+ u64 ctxid = DECODE_CTXID(resize->context_id),
+ rctxid = resize->context_id;
+
+ struct sisl_rht_entry *rhte;
+
+ int rc = 0;
+
+ /*
+ * The requested size (req_size) is always assumed to be in 4k blocks,
+ * so we have to convert it here from 4k to chunk size.
+ */
+ nsectors = (resize->req_size * CXLFLASH_BLOCK_SIZE) / gli->blk_len;
+ new_size = DIV_ROUND_UP(nsectors, MC_CHUNK_SIZE);
+
+ pr_debug("%s: ctxid=%llu rhndl=0x%llx, req_size=0x%llx,"
+ "new_size=%llx\n", __func__, ctxid, resize->rsrc_handle,
+ resize->req_size, new_size);
+
+ if (unlikely(gli->mode != MODE_VIRTUAL)) {
+ pr_debug("%s: LUN mode does not support resize! (%d)\n",
+ __func__, gli->mode);
+ rc = -EINVAL;
+ goto out;
+
+ }
+
+ if (!ctxi) {
+ ctxi = get_context(cfg, rctxid, lli, CTX_CTRL_ERR_FALLBACK);
+ if (unlikely(!ctxi)) {
+ pr_debug("%s: Bad context! (%llu)\n", __func__, ctxid);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ put_ctx = true;
+ }
+
+ rhte = get_rhte(ctxi, rhndl, lli);
+ if (unlikely(!rhte)) {
+ pr_debug("%s: Bad resource handle! (%u)\n", __func__, rhndl);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if (new_size > rhte->lxt_cnt)
+ rc = grow_lxt(afu, sdev, ctxid, rhndl, rhte, &new_size);
+ else if (new_size < rhte->lxt_cnt)
+ rc = shrink_lxt(afu, sdev, rhndl, rhte, ctxi, &new_size);
+
+ resize->hdr.return_flags = 0;
+ resize->last_lba = (new_size * MC_CHUNK_SIZE * gli->blk_len);
+ resize->last_lba /= CXLFLASH_BLOCK_SIZE;
+ resize->last_lba--;
+
+out:
+ if (put_ctx)
+ put_context(ctxi);
+ pr_debug("%s: resized to %lld returning rc=%d\n",
+ __func__, resize->last_lba, rc);
+ return rc;
+}
+
+int cxlflash_vlun_resize(struct scsi_device *sdev,
+ struct dk_cxlflash_resize *resize)
+{
+ return _cxlflash_vlun_resize(sdev, NULL, resize);
+}
+
+/**
+ * cxlflash_restore_luntable() - Restore LUN table to prior state
+ * @cfg: Internal structure associated with the host.
+ */
+void cxlflash_restore_luntable(struct cxlflash_cfg *cfg)
+{
+ struct llun_info *lli, *temp;
+ u32 chan;
+ u32 lind;
+ struct afu *afu = cfg->afu;
+ struct sisl_global_map __iomem *agm = &afu->afu_map->global;
+
+ mutex_lock(&global.mutex);
+
+ list_for_each_entry_safe(lli, temp, &cfg->lluns, list) {
+ if (!lli->in_table)
+ continue;
+
+ lind = lli->lun_index;
+
+ if (lli->port_sel == BOTH_PORTS) {
+ writeq_be(lli->lun_id[0], &agm->fc_port[0][lind]);
+ writeq_be(lli->lun_id[1], &agm->fc_port[1][lind]);
+ pr_debug("%s: Virtual LUN on slot %d id0=%llx, "
+ "id1=%llx\n", __func__, lind,
+ lli->lun_id[0], lli->lun_id[1]);
+ } else {
+ chan = PORT2CHAN(lli->port_sel);
+ writeq_be(lli->lun_id[chan], &agm->fc_port[chan][lind]);
+ pr_debug("%s: Virtual LUN on slot %d chan=%d, "
+ "id=%llx\n", __func__, lind, chan,
+ lli->lun_id[chan]);
+ }
+ }
+
+ mutex_unlock(&global.mutex);
+}
+
+/**
+ * init_luntable() - write an entry in the LUN table
+ * @cfg: Internal structure associated with the host.
+ * @lli: Per adapter LUN information structure.
+ *
+ * On successful return, a LUN table entry is created.
+ * At the top for LUNs visible on both ports.
+ * At the bottom for LUNs visible only on one port.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int init_luntable(struct cxlflash_cfg *cfg, struct llun_info *lli)
+{
+ u32 chan;
+ u32 lind;
+ int rc = 0;
+ struct afu *afu = cfg->afu;
+ struct sisl_global_map __iomem *agm = &afu->afu_map->global;
+
+ mutex_lock(&global.mutex);
+
+ if (lli->in_table)
+ goto out;
+
+ if (lli->port_sel == BOTH_PORTS) {
+ /*
+ * If this LUN is visible from both ports, we will put
+ * it in the top half of the LUN table.
+ */
+ if ((cfg->promote_lun_index == cfg->last_lun_index[0]) ||
+ (cfg->promote_lun_index == cfg->last_lun_index[1])) {
+ rc = -ENOSPC;
+ goto out;
+ }
+
+ lind = lli->lun_index = cfg->promote_lun_index;
+ writeq_be(lli->lun_id[0], &agm->fc_port[0][lind]);
+ writeq_be(lli->lun_id[1], &agm->fc_port[1][lind]);
+ cfg->promote_lun_index++;
+ pr_debug("%s: Virtual LUN on slot %d id0=%llx, id1=%llx\n",
+ __func__, lind, lli->lun_id[0], lli->lun_id[1]);
+ } else {
+ /*
+ * If this LUN is visible only from one port, we will put
+ * it in the bottom half of the LUN table.
+ */
+ chan = PORT2CHAN(lli->port_sel);
+ if (cfg->promote_lun_index == cfg->last_lun_index[chan]) {
+ rc = -ENOSPC;
+ goto out;
+ }
+
+ lind = lli->lun_index = cfg->last_lun_index[chan];
+ writeq_be(lli->lun_id[chan], &agm->fc_port[chan][lind]);
+ cfg->last_lun_index[chan]--;
+ pr_debug("%s: Virtual LUN on slot %d chan=%d, id=%llx\n",
+ __func__, lind, chan, lli->lun_id[chan]);
+ }
+
+ lli->in_table = true;
+out:
+ mutex_unlock(&global.mutex);
+ pr_debug("%s: returning rc=%d\n", __func__, rc);
+ return rc;
+}
+
+/**
+ * cxlflash_disk_virtual_open() - open a virtual disk of specified size
+ * @sdev: SCSI device associated with LUN owning virtual LUN.
+ * @arg: UVirtual ioctl data structure.
+ *
+ * On successful return, the user is informed of the resource handle
+ * to be used to identify the virtual LUN and the size (in blocks) of
+ * the virtual LUN in last LBA format. When the size of the virtual LUN
+ * is zero, the last LBA is reflected as -1.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+int cxlflash_disk_virtual_open(struct scsi_device *sdev, void *arg)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct device *dev = &cfg->dev->dev;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+
+ struct dk_cxlflash_uvirtual *virt = (struct dk_cxlflash_uvirtual *)arg;
+ struct dk_cxlflash_resize resize;
+
+ u64 ctxid = DECODE_CTXID(virt->context_id),
+ rctxid = virt->context_id;
+ u64 lun_size = virt->lun_size;
+ u64 last_lba = 0;
+ u64 rsrc_handle = -1;
+
+ int rc = 0;
+
+ struct ctx_info *ctxi = NULL;
+ struct sisl_rht_entry *rhte = NULL;
+
+ pr_debug("%s: ctxid=%llu ls=0x%llx\n", __func__, ctxid, lun_size);
+
+ /* Setup the LUNs block allocator on first call */
+ mutex_lock(&gli->mutex);
+ if (gli->mode == MODE_NONE) {
+ rc = init_vlun(lli);
+ if (rc) {
+ dev_err(dev, "%s: call to init_vlun failed rc=%d!\n",
+ __func__, rc);
+ rc = -ENOMEM;
+ goto err0;
+ }
+ }
+
+ rc = cxlflash_lun_attach(gli, MODE_VIRTUAL, true);
+ if (unlikely(rc)) {
+ dev_err(dev, "%s: Failed to attach to LUN! (VIRTUAL)\n",
+ __func__);
+ goto err0;
+ }
+ mutex_unlock(&gli->mutex);
+
+ rc = init_luntable(cfg, lli);
+ if (rc) {
+ dev_err(dev, "%s: call to init_luntable failed rc=%d!\n",
+ __func__, rc);
+ goto err1;
+ }
+
+ ctxi = get_context(cfg, rctxid, lli, 0);
+ if (unlikely(!ctxi)) {
+ dev_err(dev, "%s: Bad context! (%llu)\n", __func__, ctxid);
+ rc = -EINVAL;
+ goto err1;
+ }
+
+ rhte = rhte_checkout(ctxi, lli);
+ if (unlikely(!rhte)) {
+ dev_err(dev, "%s: too many opens for this context\n", __func__);
+ rc = -EMFILE; /* too many opens */
+ goto err1;
+ }
+
+ rsrc_handle = (rhte - ctxi->rht_start);
+
+ /* Populate RHT format 0 */
+ rhte->nmask = MC_RHT_NMASK;
+ rhte->fp = SISL_RHT_FP(0U, ctxi->rht_perms);
+
+ /* Resize even if requested size is 0 */
+ marshal_virt_to_resize(virt, &resize);
+ resize.rsrc_handle = rsrc_handle;
+ rc = _cxlflash_vlun_resize(sdev, ctxi, &resize);
+ if (rc) {
+ dev_err(dev, "%s: resize failed rc %d\n", __func__, rc);
+ goto err2;
+ }
+ last_lba = resize.last_lba;
+
+ if (virt->hdr.flags & DK_CXLFLASH_UVIRTUAL_NEED_WRITE_SAME)
+ ctxi->rht_needs_ws[rsrc_handle] = true;
+
+ virt->hdr.return_flags = 0;
+ virt->last_lba = last_lba;
+ virt->rsrc_handle = rsrc_handle;
+
+out:
+ if (likely(ctxi))
+ put_context(ctxi);
+ pr_debug("%s: returning handle 0x%llx rc=%d llba %lld\n",
+ __func__, rsrc_handle, rc, last_lba);
+ return rc;
+
+err2:
+ rhte_checkin(ctxi, rhte);
+err1:
+ cxlflash_lun_detach(gli);
+ goto out;
+err0:
+ /* Special common cleanup prior to successful LUN attach */
+ cxlflash_ba_terminate(&gli->blka.ba_lun);
+ mutex_unlock(&gli->mutex);
+ goto out;
+}
+
+/**
+ * clone_lxt() - copies translation tables from source to destination RHTE
+ * @afu: AFU associated with the host.
+ * @blka: Block allocator associated with LUN.
+ * @ctxid: Context ID of context owning the RHTE.
+ * @rhndl: Resource handle associated with the RHTE.
+ * @rhte: Destination resource handle entry (RHTE).
+ * @rhte_src: Source resource handle entry (RHTE).
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int clone_lxt(struct afu *afu,
+ struct blka *blka,
+ ctx_hndl_t ctxid,
+ res_hndl_t rhndl,
+ struct sisl_rht_entry *rhte,
+ struct sisl_rht_entry *rhte_src)
+{
+ struct sisl_lxt_entry *lxt;
+ u32 ngrps;
+ u64 aun; /* chunk# allocated by block allocator */
+ int i, j;
+
+ ngrps = LXT_NUM_GROUPS(rhte_src->lxt_cnt);
+
+ if (ngrps) {
+ /* allocate new LXTs for clone */
+ lxt = kzalloc((sizeof(*lxt) * LXT_GROUP_SIZE * ngrps),
+ GFP_KERNEL);
+ if (unlikely(!lxt))
+ return -ENOMEM;
+
+ /* copy over */
+ memcpy(lxt, rhte_src->lxt_start,
+ (sizeof(*lxt) * rhte_src->lxt_cnt));
+
+ /* clone the LBAs in block allocator via ref_cnt */
+ mutex_lock(&blka->mutex);
+ for (i = 0; i < rhte_src->lxt_cnt; i++) {
+ aun = (lxt[i].rlba_base >> MC_CHUNK_SHIFT);
+ if (ba_clone(&blka->ba_lun, aun) == -1ULL) {
+ /* free the clones already made */
+ for (j = 0; j < i; j++) {
+ aun = (lxt[j].rlba_base >>
+ MC_CHUNK_SHIFT);
+ ba_free(&blka->ba_lun, aun);
+ }
+
+ mutex_unlock(&blka->mutex);
+ kfree(lxt);
+ return -EIO;
+ }
+ }
+ mutex_unlock(&blka->mutex);
+ } else {
+ lxt = NULL;
+ }
+
+ /*
+ * The following sequence is prescribed in the SISlite spec
+ * for syncing up with the AFU when adding LXT entries.
+ */
+ dma_wmb(); /* Make LXT updates are visible */
+
+ rhte->lxt_start = lxt;
+ dma_wmb(); /* Make RHT entry's LXT table update visible */
+
+ rhte->lxt_cnt = rhte_src->lxt_cnt;
+ dma_wmb(); /* Make RHT entry's LXT table size update visible */
+
+ cxlflash_afu_sync(afu, ctxid, rhndl, AFU_LW_SYNC);
+
+ pr_debug("%s: returning\n", __func__);
+ return 0;
+}
+
+/**
+ * cxlflash_disk_clone() - clone a context by making snapshot of another
+ * @sdev: SCSI device associated with LUN owning virtual LUN.
+ * @clone: Clone ioctl data structure.
+ *
+ * This routine effectively performs cxlflash_disk_open operation for each
+ * in-use virtual resource in the source context. Note that the destination
+ * context must be in pristine state and cannot have any resource handles
+ * open at the time of the clone.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+int cxlflash_disk_clone(struct scsi_device *sdev,
+ struct dk_cxlflash_clone *clone)
+{
+ struct cxlflash_cfg *cfg = (struct cxlflash_cfg *)sdev->host->hostdata;
+ struct llun_info *lli = sdev->hostdata;
+ struct glun_info *gli = lli->parent;
+ struct blka *blka = &gli->blka;
+ struct afu *afu = cfg->afu;
+ struct dk_cxlflash_release release = { { 0 }, 0 };
+
+ struct ctx_info *ctxi_src = NULL,
+ *ctxi_dst = NULL;
+ struct lun_access *lun_access_src, *lun_access_dst;
+ u32 perms;
+ u64 ctxid_src = DECODE_CTXID(clone->context_id_src),
+ ctxid_dst = DECODE_CTXID(clone->context_id_dst),
+ rctxid_src = clone->context_id_src,
+ rctxid_dst = clone->context_id_dst;
+ int adap_fd_src = clone->adap_fd_src;
+ int i, j;
+ int rc = 0;
+ bool found;
+ LIST_HEAD(sidecar);
+
+ pr_debug("%s: ctxid_src=%llu ctxid_dst=%llu adap_fd_src=%d\n",
+ __func__, ctxid_src, ctxid_dst, adap_fd_src);
+
+ /* Do not clone yourself */
+ if (unlikely(rctxid_src == rctxid_dst)) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if (unlikely(gli->mode != MODE_VIRTUAL)) {
+ rc = -EINVAL;
+ pr_debug("%s: Clone not supported on physical LUNs! (%d)\n",
+ __func__, gli->mode);
+ goto out;
+ }
+
+ ctxi_src = get_context(cfg, rctxid_src, lli, CTX_CTRL_CLONE);
+ ctxi_dst = get_context(cfg, rctxid_dst, lli, 0);
+ if (unlikely(!ctxi_src || !ctxi_dst)) {
+ pr_debug("%s: Bad context! (%llu,%llu)\n", __func__,
+ ctxid_src, ctxid_dst);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if (unlikely(adap_fd_src != ctxi_src->lfd)) {
+ pr_debug("%s: Invalid source adapter fd! (%d)\n",
+ __func__, adap_fd_src);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /* Verify there is no open resource handle in the destination context */
+ for (i = 0; i < MAX_RHT_PER_CONTEXT; i++)
+ if (ctxi_dst->rht_start[i].nmask != 0) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /* Clone LUN access list */
+ list_for_each_entry(lun_access_src, &ctxi_src->luns, list) {
+ found = false;
+ list_for_each_entry(lun_access_dst, &ctxi_dst->luns, list)
+ if (lun_access_dst->sdev == lun_access_src->sdev) {
+ found = true;
+ break;
+ }
+
+ if (!found) {
+ lun_access_dst = kzalloc(sizeof(*lun_access_dst),
+ GFP_KERNEL);
+ if (unlikely(!lun_access_dst)) {
+ pr_err("%s: Unable to allocate lun_access!\n",
+ __func__);
+ rc = -ENOMEM;
+ goto out;
+ }
+
+ *lun_access_dst = *lun_access_src;
+ list_add(&lun_access_dst->list, &sidecar);
+ }
+ }
+
+ if (unlikely(!ctxi_src->rht_out)) {
+ pr_debug("%s: Nothing to clone!\n", __func__);
+ goto out_success;
+ }
+
+ /* User specified permission on attach */
+ perms = ctxi_dst->rht_perms;
+
+ /*
+ * Copy over checked-out RHT (and their associated LXT) entries by
+ * hand, stopping after we've copied all outstanding entries and
+ * cleaning up if the clone fails.
+ *
+ * Note: This loop is equivalent to performing cxlflash_disk_open and
+ * cxlflash_vlun_resize. As such, LUN accounting needs to be taken into
+ * account by attaching after each successful RHT entry clone. In the
+ * event that a clone failure is experienced, the LUN detach is handled
+ * via the cleanup performed by _cxlflash_disk_release.
+ */
+ for (i = 0; i < MAX_RHT_PER_CONTEXT; i++) {
+ if (ctxi_src->rht_out == ctxi_dst->rht_out)
+ break;
+ if (ctxi_src->rht_start[i].nmask == 0)
+ continue;
+
+ /* Consume a destination RHT entry */
+ ctxi_dst->rht_out++;
+ ctxi_dst->rht_start[i].nmask = ctxi_src->rht_start[i].nmask;
+ ctxi_dst->rht_start[i].fp =
+ SISL_RHT_FP_CLONE(ctxi_src->rht_start[i].fp, perms);
+ ctxi_dst->rht_lun[i] = ctxi_src->rht_lun[i];
+
+ rc = clone_lxt(afu, blka, ctxid_dst, i,
+ &ctxi_dst->rht_start[i],
+ &ctxi_src->rht_start[i]);
+ if (rc) {
+ marshal_clone_to_rele(clone, &release);
+ for (j = 0; j < i; j++) {
+ release.rsrc_handle = j;
+ _cxlflash_disk_release(sdev, ctxi_dst,
+ &release);
+ }
+
+ /* Put back the one we failed on */
+ rhte_checkin(ctxi_dst, &ctxi_dst->rht_start[i]);
+ goto err;
+ }
+
+ cxlflash_lun_attach(gli, gli->mode, false);
+ }
+
+out_success:
+ list_splice(&sidecar, &ctxi_dst->luns);
+ sys_close(adap_fd_src);
+
+ /* fall through */
+out:
+ if (ctxi_src)
+ put_context(ctxi_src);
+ if (ctxi_dst)
+ put_context(ctxi_dst);
+ pr_debug("%s: returning rc=%d\n", __func__, rc);
+ return rc;
+
+err:
+ list_for_each_entry_safe(lun_access_src, lun_access_dst, &sidecar, list)
+ kfree(lun_access_src);
+ goto out;
+}
Code Review / kvmfornfv.git / blobdiff